Air line lubricator



June 8, 1954 R. E. JOHNSON AIR LINE LUBRICATOR Filed Feb. 8. 1952 INVENTOR. ji gflm ATTORNEYS.

Patented June 8, 1954 UNITED STATES PATENT OFFICE 2,680,496 AIR LINE LUBRICATOR Ralph E. Johnson,

Arrow Tools, Inc., of Illinois Application February 8, 1952, Serial No.

13 Claims.

This invention relates to devices for delivery of uid into the quantity of lubricant entering the air stream so as to keep the quantity of lubricant per volume of cessful.

Wick type lubricators have been employed in an effort to accomplish these purposes with some degree of success. In these, a portion of the wick more or less lubricant through the the air stream.

Also, these structures suffer the disadvantage that the capillary action of the wick continues during periods of inoperation of the pneumatic Wheaten, Ill., assignor to Chicago, 111., a corporation 2 equipment and results in saturation of the Wick and the forming of a heavy coating of lubricant on its surface.

over-lubrication and improper lubrication results. These lubricators failed then to accomplish the they were used.

prov1de an air line lubricator in which the quanment.

A further object of means to accomplish matically as an integral feature of my lubricator.

livery of lubricant into the air stream as globules or large drops when the equipment is next placed in operation is thereby prevented.

Yet another object of my invention is to provide a lubricator in which the lower surface of the lubricant feeder is subjected to a vacuum caused by the falling of the lubricant in the lubricant supplv tube when the flow of air in the air supply line is terminated and the pressure on the lubricant in the reservoir decreases.

A further object is to provide a lubricator in which sudden flooding oi the air stream with lubricant is eliminated.

A still further object of this invention is to provide an air-line lubricator in which the passage through which air is delivered has a restricted intermediate portion formed by the inward projections of the side walls of the passage to a point almost contacting the lubricant feeder extending into the passage so that the flow of air is over from the top of the feeder and delivery of lubricant into the air stream is primarily a function of the pressure difference between the upstream and restricted portion of the passage.

A still further object of this invention is to provide a positive orifice, the size of which may be positively adjusted, through which the air must flow, thereby giving accurate and positive control of the pressure differential across the orifice with the result that the quantity of lubricant evaporated into the air stream may be accurately adjusted.

Still a further object is to provide a positive orifice in which the size of the orifice is determined by the axial position of the lubricant feeder in the air passage. The term positive orifice is used to mean an orifice of variable size in which the size of the opening is positively or accurately adjustable to provide an orifice of required size.

Additional objects and advantages of this invention will appear as the specification proceeds.

My invention can best be understood by reference to the drawings in which- Figure l is an end view in elevation of the lubricator comprising my invention;

Figure 2 '15 a vertical sectional view taken on the line 2--2 of Figure 1 showing the lubricant out of contact with the feeder means during periods of inoperation; and

Figure 3 is a top sectional view taken on the line of 33 of Figure 1.

In the illustration given, a reservoir 10 is provided in a container or bowl lUa supported on a housing or cap ll, having a threaded portion I2, by a fitting or nut IS. A sealing gasket M is interposed between the reservoir l and the housing ll. lhe it may be easily gripped for tightening. A filler plug IE is provided in the upper portion of the housing H for introduction of a lubricant into the reservoir. A. sealing gasket or O-ring I511 is positioned between the housing H and the filler plug 16. The reservoir I!) may be of any general shape and formed from any desired material. In the preferred embodiment of my invention 1 use a transparent plastic which is not easily broken and through which the contents of the reservoir and the positioning of the lubricant feeder (to be described later) are easily visible.

The housing l i has a passage l1 running longitudinally therethrough in which threaded portions 18 are provided at each end so that the housing may be interposed and fastened in the air delivery line of pneumatic equipment with which the lubricator is used. A small transverse passage or aperture 20 opens into the bottom of the high pressure side or upstream side of the longitudinal passage 11 and communicates with the reservoir to.

The cross-sectional area of the passage 1'! is decreased at the central portion to form a refitting H has knurls l so that in the passage as shown more clearly in Figure 3. Restricting the passage IT at some intermediate point, the central portion in the illustration, and introducing the lubricant feeder into the passage at the restricted area results in a greater pressure differential between the point at which the feeder enters the passage and that portion of the passage lying upstream of the feeder. The pressure differential results from the difference of the velocity of flow of the air stream through the enlarged and restricted portions of the passage. The velocity is greater through the restricted portion and a lower pressure accompanies the increase in the velocity.

In the preferred embodiment of my invention, the restriction comprises an orifice, the size of which may be positively varied and controlled. The orifice (Fig. l) is generally rectangular in shape and is formed by the inwardly extending projections IBc of the passage side walls and the lubricant feeder. The width of the passage between the projections IBd is somewhat less than the diameter or width of the lubricant feeder. As seen in Figure 3, the lubricant feeder extends into the passage 1'! adjacent the restricted portion l9 and on the down stream side thereof. Therefore, the air flowing through the passage must pass over the top portion of the feeder and it is seen that the size of the orifice provided by the projections lea and the feeder is adjusted by changing the axial position of the feeder within the passage. It has been found that this arrangement is particularly successful in controlling or regulating the quantity of lubricant evaporated into the air stream. Since the size of the orifice may be positively determined, the velocity of flow of the air through the restricted portion 18 of the passage and through the orifice may be accurately regulated. This results in an accurate regulation of the pressure difierential existing between the upstream portion of the passage and the restricted portion of the passage or point at which the lubricant feeder enters the passa e.

This arrangement is also successful in caus ing the lubricant to enter the air stream in the form of extremely fine particles or as a very fine mist. This permits the lubricant to be ideally dispersed throughout the air stream. However, it is to be understood that the passage l1 could be of constant diameter throughout; the lubricant feeder extending into the passage I1 providing a sufficient restriction to create a pressure difierential between different portions of passage H to produce satisfactory results. Also, the size of the restriction l9 could be some value between the constant diameter passage and that shown in Figure 3.

A bore 2| having an enlarged, threaded portion 22 is provided through the lower central part of the housing It and extends between the restriction IQ of the passage H and the reservoir Ill. In the preferred embodiment, the bore 2| is adjacent the restriction 19 at the down stream side thereof. A bolt 23 having a. threaded end 24, a head 25, and a bore 26 extending longitudi nally therethrough is adapted to enter the threaded portion 22 of the bore 2i and to be ad justed axially therein. A look nut 21 having side extensions 28 adapted to receive the head 25 of the bolt 23 screws onto the threaded end 24 of the bolt 23 and may be tightened against the housing ll to lock the bolt 23 in axial adjustment. A sealing gasket 29 is interposed bestricted section 1 9 2,680,496 tween the locking nut 21 and the housing H. into the reservoir I through the filler plug IS The lock nut 21 ha a chamiered portion 290: until the lower portion of the tube 30 is subinto which the gasket 29 is squeezed upon tightmerged. ening of the lock nut 2'! against the hous ng l When air under pressure is placed in the air ereby providing a tighter seal 5 delivery line of the equipment with which the length to extendinto the fluid contained in the to the flow of air downwardly through it and so that it is easily seen, through the transparent tion of equilibrium is reached.

reservoir, when fluid is in the tube. As air flows in the air delivery line, the rectric- A lubricant feeder 3| is adapted to be insei ted tion l9 implemented by the resistance to the into the bore 26 of the bolt 23 at the threaded end ow of air caused by the extension of the feeder such as an adhesive or a press fit. The lubricant 2o ferential between the point at which the aperii the passage l1 when the bolt 23 is adjusted sure point of the passage. Thus, air in the tube axially to the most advanced position. In the 30 will be expelled through the feeder 3| and preferred embodiment of my invention I use a fluid will rise in the tube 30 and into contact lubricant feeder made from porous or powdered with the feeder 31 where it is carried into the bronze. However feeders made from many 3( restriction l9 by both the capillary action of the porous materials are suitable. For example, p u feeder 3| d the pressure of the fl feeders of other porous metals, such as powdered in the tube 30 pushing upwards against the iron, may readil be us d; porous, n et lli porous feeder 3|. Because of the fine porosity substances are suitable; the only requirement is of the feeder 3!, the lubricant 1S broken down into that fluid can be transferred through the feeder. 3; fi y d ided pa c s. It is picked up y the markings 32 at each corner. These markings into the pneumatic equipment in the form of a are employed in conjunction with the side exfine spray or mist.

tensions 28 of the lock nut 21 and therewith form When the air flow is subsequently pp the an indicator, the use of which permits the length 41' pressure in the reservoir immediately decreases of the feeder 3| extending into the passage l7 and the fluid in the tube 30 immediately drops permit viewing of the upper markings 32 i ,11 and a coating of lubricant will not form on the positions of axial adjustment of the bolt 23. surface of the feeder during i d of i Thus, any length of the feeder 3| extending into Operationthe restriction I9 is easily determined by compar- Due to e c nstruction of the lubricator, the

Since the head 25 of the bolt 23 is received air increases, the quantity of lubricant increases within the side extensions 28 of the locking nut and Vice The reasons for this r at tity of lubricant evaporated into the air stream.

once the desired axial adjustment of the bolt 23 9 e increased Y Will hecessitete relative to the lower edge of side extension 28 an Increase h Y F of the passing is set, the two are turned together until the lockthrough the resmctmn m the passage An ing nut is tightened securely against the housing in n e in e a velocity of a fluid h as air passing a liquid film, as a lubricating oil, is

accuses of the air passing through the restriction It will cause a greater pressure difierential to exist between the point at which the feeder 3i enters passage 11 and the point at which the aperture 20 is located. This increase in pressure differential will be reflected as a like increase of the pressure in the reservoir ill. A greater pressure will therefore be exerted by the lubricant in the tube 30 against and into the porous feeder 3!, thereby causing a greater quantity of fluid to be delivered into the air stream. Thus, by utilizing the resulting change in pressure differential caused by a change in air volume delivered through passage H, the quantity of lubricant introduced into the air stream is caused to remain nearly constant per volume of our used.

In the preferred embodiment of my invention which utilizes the positive orifice, the quantity of lubricant evaporated from the feeder ill will be primarily a reflection of the pressure differential existing in the passage ll. Lubricant will be evaporated into the air stream from the top of the feeder and will also enter the air stream from the downstream surface of the feeder oecause of the lower pressure at that point. How

ever, since the airstream passes parallel to the top of the feeder 3i and does not impinge directly upon the downstream portion of the feeder, an increase in the mass velocity of flow increases the rate of evaporation per given mass or volume of 1 air only a small amount. Therefore, quantity regulation is very accurately controlled because the amount of lubricant reaching the evaporation surface of the feeder 3i depends almost wholly upon the pressure urging the lubricant through the pores of the feeder. As previously stated, the pressure differential in the passage is related to the difference in air velocity through the pas sage and orifice. The velocity of flow through the orifice increases as the orifice size decreases and the pressure at the orifice (and feeder) do creases with the increase in velocity. Thus, raising the feeder decreases the orifice size which in turn creates a greater pressure differential with the result that more lubricant is forced 7 through the feeder and dispersed into the air stream. Accurate regulation is thereby obtained since the external factors usually influencing the amount of lubricant dispensed into the air stream have been eliminated.

The quantity of lubricant delivered for any one setting of the feeder adjustment may be varied by using lighter or heavier lubricant, and also by using feeders having greater or lesser porosity.

With a given feeder, lubricant viscosity, and

air volume, the quantity of lubricant delivered into the air stream may be varied by simply changing the length of the feeder 3| extending into the passage l1. This is easily accomplished by simply changin the axial adjustment of the bolt 23. Thus, as the size of the equipment, work conditions, or type of work being done is changed, the quantity of lubricant supplied to the air stream is easily regulated to correspond to the demand.

Providing the feeder adjusting means within the reservoir prohibits accidental changing of the setting. Yet, the position of the setting is easily determined by viewing it through the transparent wall of the reservoir Ill. The reservoir Ill is easily detached. from the housing ll making the bolt 23 readily available if it is desired to change the feeder setting,

In the preferred embodiment of my invention, I use a transparent reservoir l0 and a transparent tube 30. It is, therefore, possible to determine whether the lubricator is functioning properly by simply looking through the transparent side wall and into the reservoir Hi to see whether the fluid has been forced upward in the transparent tube 30. If fluid is not in the tube 80 and the equipment is in operation, the lubricator is not functioning. Since air line lubricators are prone to improper operation from such things as air leaks resulting from insufficient tightening of the various fittings, this is a desirable advanage.

In the lubricator of my invention, the only surface of the feeder Si in contact with reservoir lubricant is the bottom or lower end surface thereof and this contact occurs only when the lubricator is in operation. Thus, the quantity of lubricant evaporated into the air stream is independent of the level of lubricant within the reservoir with the result that greater accuracy and control over the amount of lubricant entering the air stream is obtained.

While, in the foregoing specification, I have set forth a specific structure in considerable detail for the purpose of illustrating one embodiment of the invention, it will be understood that such details of structure and means may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

1. An air line lubricator, comprising a contalner providing a reservoir for lubricating fluid, a housing secured to said container, said housing providing a passage for the flow of air therethrough, a bore in communication between said passage and said reservoir, feeder means mounted within said bore and extending into said passage and the lower portion of said feeder means terminating above the level of the lubricating fluid, a tube extending downwardly into said reservoir so that the lower end thereof is immersed within the lubricatin fluid in said reservoir, and means connecting the upper end of said tube with the lower end of said feeder means, said housing also providing an aperture in open communication between said passage and said reservoir, said passage having a restricted portion adjacent said bore and feeder to provide an opening of slightly smaller cross section than the width of said feeder.

2. An air line lubricator, comprising a container providing a reservoir for lubricating fluid. a housing secured to said container, said housing providing a passage for the flow of air therethrough, a bore in communication between an intermediate point in said passage and said reservoir, feeder means adapted to have a lubricant pass therethrough mounted within said bore and extending into said passage and the lower portion of said feeder means terminating above the level of the lubricating fluid, a tube extending downwardly into said reservoir so that the lower end thereof is immersed within the lubricating fluid in said reservoir, means connecting the upper end of said tube with the lower end of said feeder means, said housing also providing an aperture in open communication between said passage and said reservoir, the side walls of said passage having restrictions adjacent said bore and feeder to form an opening of slightly smaller cross section than the width of said feeder to provide with said feeder an orifice through which the air must flow.

3. An air line lubricator comprising a contain- I er providing a reservoir for lubricating fluid. a

to said container, said housing oi air therehousing secured providing a passage for the flow through, a bore sage extendin inwardly adjacent said bore and is determined by within said passage.

5. An air line lubricator comprising a. container providing a. reservoir for lubricating fluid, a housin said tube recedes out of contact with said feeder means.

7. The structure of claim 6 in feeder means is mounted in said bore in sealing adapted to be interposed in an air line to supply lubricant to the feeder means extending into said passage and the lower portion of said feeder means terminating above the level of the lubricating fluid, a tube extending downwardly into said reservoir so that the lower end thereof can be immersed within the lubricating fluid in said reservoir, means connecting the upper end of said tube with the lower end of said feeder means so that said lubricating fluid can ascend said tube and pass into said feeder means, said housing also providing an aperture in open communication between a point in the upstream portion of said passage and said reservoir, whereby when a stream of air is forced through said passage, the pressure within said passage is transferred through said aperture to the surface of said lubricating fluid, while at the same time the transfer of said pressure to the inside of said tube is limited by said feeder means with the result that said lubricating fluid rises in said tube until it contacts said feeder means and passes therethrough to its exposed outer surface where it is picked up by said air stream, and thereafter, when the flow of air in said passage is terminated, the lubricating fluid in said tube recedes out of contact with said feeder means.

9. The structure of claim 8 in which said feeder means is mounted in said bore in sealing relationship therewith, whereby air cannot enter into said tube from between the said feeder means and said bore, and when the flow of air in said passage is terminated, the lubricating fluid remain, ing in said feeder means is sucked back into said tube by the falling of the fluid within said tube.

10. The structure of claim 9 in which said bore connects a point in said restricted portion ofsaid passage with said reservoir, and in which said aperture is positioned adjacent said restricted portion of said passage on the upstream side thereof.

11. The structure of claim 9 in which said container providing a reservoir therein is detachable from said housing, and in which means are provided from within said container to adjust the length of said feeder means extending into said passage.

12. The structure of claim 9 feeder means is a porous metal.

13. The structure of claim 9 in which said feeder means is a sintered material.

in which said References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,990,524 Bystricky Feb. 12, 1935 2,229,176 Kehle Jan. 21, 194A 2,515,417 Myers July 18, 1950 

